Web winding apparatus



Fb 14, 1967 R. H. B. BuTEux ETAL 3,304,017

wEB wINDING APPARATUS Filed Dec. 14, 1964 United States Patent O 3,304,017 WEB WINDING APPARATUS Richard Harold Barclay Buteux, Welwyn Garden City,

and Charles Hampden Crooks, Welwyn, England, assignors to Imperial Chemical Industries Limited, London, England, a corporation of Great Britain Filed Dec. 14, 1964, Ser. No. 418,208 Claims priority, application Great Britain, Dec. 13, 1963, 49,337/ 63 5 Claims. (Cl. 242-55) This invention relates to an improved web winding apparatus.

There is a tendency when winding up reels of web material, such as plastic films of, for example, polyethylene terephthalate, for air to be trapped between the individual layers of wound-up material. This results in loosely wound reels which are unsatisfactory for commercial exploitation. Conventional winding machines attempt to overcome this difiiculty by providing means for winding up the web under such a high tension that deformations are introduced into the material which permanently spoil it, and this is particularly true in the case of thin plastic films. One way of overcoming this drawback is to allow the weight of a roll bearing on the circumfe-rence of the wound-up layers where the newly fed web first contacts them to express the air from the gap between them and the newly fed web, whilst providing means for allowing this roll to move away from the wound-up layers as they increase in number. This technique suffers from the disadvantage that, because in practice the webs show unintentional thickness variations, means have to be provided for making appropriate adjustments to the position of the lay-on rolls. Further, if the latter are rubber-surfaced they will tend to suffer `from surface wear and abrasion and their usefulness will be relatively short-lived. In such cases, not only is the cost and inconvenience of replacing them a disadvantage, but the time wasted while the equipment remains idle during their replacement is also serious.

It is an object of the present invention to provide an improved apparatus for winding up reels of web material which does not suffer from the above-mentioned defects.

Our invention therefore consists of an improved apparatus for winding up a continuous length of web material on the circumference of a rotating cylindrical support on to which the web is fed wherein a stream of gas inert with respect to said web material fed from an orifice is directed across the width of the web so that as each portion of the web comes in contact with the outermost wound layer it is forced on to said layer, which comprises allowing the position of the orifice relative to the portion of the web where it comes into contact with said layer, to be maintained substantially constant during the winding operation by the action of the stream of gas issuing from the orifice and directed on to said web.

We also provide an apparatus for winding up continuous lengths of web material which comprises means for supporting and rotating a core member to thereby form a roll of said web material when said material is fed to said core member, and also a device located for directing a stream of gas from an orifice in the device across the width of the web where the web being fed initially makes contact with the outermost layer of the web on said core member, said device being mounted such that said orifice is normally urged towards said web, and the device being connectable to a source of gas under pressure whereby gas is caused to issue from said orifice to provide a force sufficient to maintain 'said orifice at a substantially constant distance from said web being fed.

One specific embodiment of our invention will now be described with reference to the accompanying drawing. The latter shows a suitable form of apparatus in perspective view in which a rotatable mandrel 1 drives a reel 2 through clutch 3. A flexible pipe 5 is adapted to be connected to an air blower (not shown) at one end and the other end is fitted with a slot nozzle 6 extending across the width of the reel. The nozzle is rigidly clamped by a horizontal balance arm 7 which is pivoted around pivot shaft 8 and an adjustable counterweight 9 is attached to its opposite end.

In operating the above-described apparatus for winding up continuous film 4, the counterweight is adjusted so as to give a downward load of a pre-determined magnitude at the nozzle 6 when no air is being blown down the pipe 5. Film 4 is then attached to the reel 2 in a conventional manner, mandrel 1 is rotated, and pipe 5 is connected to the blower. As the reel increases in thickness the nozzle rises spontaneously above it by a corresponding amount so that the force expelling the air from between the layers of film remains substantially constant.

It will be appreciated that other means of counterbalancing the thrust of the air emitted from the nozzle may be used, for instance instead of a counterweight as illustrated, spring means or hydraulic pressure may be used.

Our invention has another advantage over the use of rubber or plastic lay-on rolls in that it is frequently desirable to wind up film material in widths that are greater than the length of commercially-available rubber or plastic lay-on rolls, such a limitation not applying to our use of air jets. Our invention is, of course, equally applicable to winding up films in the widths as manufactured by the normal techniques involving lateral stretching of thermoplastic films produced by extrusion, as to winding up such films which have subsequently been slit lengthwise for use in specific applications where narrow widths are required, e.g., as bases for magnetic recording tapes or typewriter ribbons.

We claim:

1. Apparatus for Winding up a continuous length of web material which comprises a core member, means for feeding the web material to said core member, means for supporting and rotating said core member whereby web material fed thereto may be wound up on said core member and further means including a gas orifice positioned to direct a stream of gas across the width of the web material at the point Where said material makes contact with the outermost layer of material wound on the core member, means for mounting said further means so that said orifice is normally urged towards said web, said further means including means for connection to a source of gas under pressure whereby gas issuing from said orifice provides a force sufficient to maintain said orifice at a substantially constant distance from the web material being fed to said core member.

2. Apparatus according to claim 1 wherein said means for moving said further means includes a pivotable support.

3. Apparatus according to claim 1 including counterweight means having a variable effective mass modifying the degree to which said orifice is normally urged towards said web.

4. Apparatus according to claim 1 including spring means modifying the degree to which said orifice is normally urged towards said web.

5. Apparatus according to claim 1 including hydraulically applied pressure means modifying the degree to which said orifice is normally urged towards said web.

References Cited by the Examiner UNITED STATES PATENTS 3,121,863 2/1964 Lovell 242-55 X FRANK I. COHEN, Primary Examiner. G. F. MAUTZ, Examinez'. 

1. APPARATUS FOR WINDING UP A CONTINUOUS LENGTH OF WEB MATERIAL WHICH COMPRISES A CORE MEMBER, MEANS FOR FEEDING THE WEB MATERIAL TO SAID CORE MEMBER, MEANS FOR SUPPORTING AND ROTATING SAID CORE MEMBER WHEREBY WEB MATERIAL FED THERETO MAY BE WOUND UP ON SAID CORE MEMBER AND FURTHER MEANS INCLUDING A GAS ORIFICE POSITIONED TO DIRECT A STREAM OF GAS ACROSS THE WIDTH OF THE WEB MATERIAL AT THE POINT WHERE SAID MATERIAL MAKES CONTACT WITH THE OUTERMOST LAYER OF MATERIAL WOUND ON THE CORE MEMBER, MEANS FOR MOUNTING SAID FURTHER MEANS SO THAT SAID ORIFICE IS NORMALLY URGED TOWARDS SAID WEB, SAID FURTHER MEANS INCLUDING MEANS FOR CONNECTION TO A SOURCE OF GAS UNDER PRESSURE WHEREBY GAS ISSUING FROM SAID ORIFICE PROVIDES A FORCE SUFFICIENT TO MAINTAIN SAID ORIFICE AT A SUBSTANTIALLY CONSTANT DISTANCE FROM THE WEB MATERIAL BEING FED TO SAID CORE MEMBER. 